Nab-paclitaxel interrupts cancer-stromal interaction through C-X-C motif chemokine 10-mediated interleukin-6 downregulation in vitro

Cancer-associated fibroblasts (CAF), derived from stroma of cancer tissues, interact with cancer cells and play an important role in cancer initiation, growth, and metastasis. Nab-paclitaxel (nab-PTX) is a 130 nm albumin-binding paclitaxel and recommended for many types of cancer chemotherapy. The nab-PTX stromal-disrupting effect during pancreatic cancer treatment has been reported. The aim of the present study was to determine the role of nab-PTX in cancer cells and CAF interaction. Cancer cells (MIA PaCa-2 and Panc-1) were cocultured with CAF or treated with CAF conditioned medium, after which their migration and invasion ability, epithelial-mesenchymal transition (EMT)-related marker expression and C-X-C motif chemokine 10 (CXCL10) expression and secretion were detected. Nab-PTX treatment was carried out during the coculture system or during preparation of CAF conditioned medium. Then cancer cell migration and invasion ability, EMT-related marker expression, CXCL10 expression and secretion, and interleukin-6 (IL-6) expression and secretion by CAF were checked After coculture with CAF, migration and invasion ability of cancer cells increased. CAF also downregulated E-cadherin and upregulated N-cadherin and vimentin expression in cancer cells. During coculture or stimulation with cancer cell-cultured medium, CAF significantly increased IL-6 expression and secretion. However, nab-PTX in the coculture system canceled CAF-induced migration and invasion promotion and EMT-related gene changes. Moreover, nab-PTX increased CXCL10 expression of cancer cells which blocked CAF IL-6 expression and secretion. Nab-PTX treatment could increase CXCL10 expression of cancer cells which blocks CAF cancer cell migration and invasion-promoting effect by inhibiting IL-6 expression.